cho biết khối lượng tính bằng gam của 1 nguyên tử Cacbon là 1,9926 . 10-23g a, 1đvC tương ứng với bao nhiêu gam b, tính khổi lượng bằng gam của 1 nguyên tử: fe,ca

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Sydney is Australia's most exciting city. The history of Australia begins here. In 1788 Captain Arthur Philips arrived in Sydney with 11 ships and 1624 passengers from Britain (including 770 prisoners). Today there are about 3.6 million people in Sydney. It is the biggest city in Australia, the busiest port in the South Pacific and one of the most beautiful cities in the world. In Sydney, the buildings are higher, the colors are brighter and the nightlife is more exciting. There are over 20 excellent beaches close to Sydney and its warm climate and cool winter have made it a favorite city for immigrants from overseas. There are two things that make Sydney famous: its beautiful harbor, the Sydney Harbor Bridge, which was built in 1932 and the Sydney Opera House, which was opened in 1973. 28. Where does the history of Australia begin? A. South Pacific B. North Pacific C. Britain D. Sydney 29. Which of the following should be the title of the reading passage? A. Sydney's Opera House B. The history of Sydney C. Sydney's beaches and harbors D. An introduction of Sydney 30. Which of the following statement is NOT true about Sydney? A. Sydney is the smallest city in Australia. B. Sydney is one of the most beautiful cities in the world. C. Sydney is the most exciting city in Australia. D. Sydney is a favorite city for immigrants from overseas. 31. How many beaches are there close to Sydney? A. Fewer than 20 beaches B. Nearly 20 beaches C. More than 20 beaches D. Less than 20 beaches 32. When was the Sydney Harbor Bridge built? A. In 1788 B. In 1932 C. In 1973 D. In 1624

Exercise 3. Read the text and answer questions. Are there intelligent beings on the planets in our solar system? Most scientists do not think so. If there are, the only likely place is Mars. It is fun to imagine our kind of humans on other worlds, but they would probably look so different we might not recognize them as people at all. Living things have a wonderful way of adapting themselves to conditions around in order to stay alive. Plants grow in the Arctic. Some simple animals can survive being boiled or frozen. Creatures live in the blackest deeps of the sea under thousands of tons of pressure. We cannot really state that our kind of air is the only kind living things could breathe or that they must have water or certain climate. Creatures that breathed other gases or lived in other temperatures, however, would not look like us. Are there people anywhere else in the universe? Maybe there are. In our own galaxy, there are billions of stars. Some must have planets with conditions like those on earth. Somewhere in space, there could be other thinking beings. If their planets are older, they may know more than we do. They may be a traveling in space. 1. Scientists think that on other planets in our solar system there are _______ A. probably some other intelligent beings. B. probably no other intelligent beings. C. certainly some other intelligent beings. D. certainly no other intelligent beings. 2. Scientists think that any intelligent beings on other planets in our solar system. A. would live under thousands of tons of pressure. B. would be very different from us. C. would already be traveling in space. D. would have adapted themselves to conditions better than we have done. 3. What do creatures do to stay alive if conditions around them change? A. to travel in space. B. to grow in the Arctic. C. to go to other worlds. D. to adapt themselves. 4. The bolded word "They" in the passage refers to A. planets. B. conditions. C. other thinking beings. D. billions of stars. 5. Other human beings live A. possibly on other planets of stars in our galaxy. B. possibly on other planets in our solar system. C. possibly on other stars in our own galaxy. D. everywhere in the universe.